granicus.if.org Git - postgresql/blob - src/backend/catalog/pg_proc.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * pg_proc.c
   4  *        routines to support manipulation of the pg_proc relation
   5  *
   6  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        $PostgreSQL: pgsql/src/backend/catalog/pg_proc.c,v 1.162 2009/03/26 22:26:06 petere Exp $
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15 #include "postgres.h"
  16
  17 #include "access/heapam.h"
  18 #include "access/xact.h"
  19 #include "catalog/dependency.h"
  20 #include "catalog/indexing.h"
  21 #include "catalog/pg_language.h"
  22 #include "catalog/pg_namespace.h"
  23 #include "catalog/pg_proc.h"
  24 #include "catalog/pg_proc_fn.h"
  25 #include "catalog/pg_type.h"
  26 #include "executor/functions.h"
  27 #include "funcapi.h"
  28 #include "mb/pg_wchar.h"
  29 #include "miscadmin.h"
  30 #include "nodes/nodeFuncs.h"
  31 #include "parser/parse_type.h"
  32 #include "tcop/pquery.h"
  33 #include "tcop/tcopprot.h"
  34 #include "utils/acl.h"
  35 #include "utils/builtins.h"
  36 #include "utils/lsyscache.h"
  37 #include "utils/syscache.h"
  38
  39
  40 Datum           fmgr_internal_validator(PG_FUNCTION_ARGS);
  41 Datum           fmgr_c_validator(PG_FUNCTION_ARGS);
  42 Datum           fmgr_sql_validator(PG_FUNCTION_ARGS);
  43
  44 static void sql_function_parse_error_callback(void *arg);
  45 static int match_prosrc_to_query(const char *prosrc, const char *queryText,
  46                                           int cursorpos);
  47 static bool match_prosrc_to_literal(const char *prosrc, const char *literal,
  48                                                 int cursorpos, int *newcursorpos);
  49
  50
  51 /* ----------------------------------------------------------------
  52  *              ProcedureCreate
  53  *
  54  * Note: allParameterTypes, parameterModes, parameterNames, and proconfig
  55  * are either arrays of the proper types or NULL.  We declare them Datum,
  56  * not "ArrayType *", to avoid importing array.h into pg_proc_fn.h.
  57  * ----------------------------------------------------------------
  58  */
  59 Oid
  60 ProcedureCreate(const char *procedureName,
  61                                 Oid procNamespace,
  62                                 bool replace,
  63                                 bool returnsSet,
  64                                 Oid returnType,
  65                                 Oid languageObjectId,
  66                                 Oid languageValidator,
  67                                 const char *prosrc,
  68                                 const char *probin,
  69                                 bool isAgg,
  70                                 bool isWindowFunc,
  71                                 bool security_definer,
  72                                 bool isStrict,
  73                                 char volatility,
  74                                 oidvector *parameterTypes,
  75                                 Datum allParameterTypes,
  76                                 Datum parameterModes,
  77                                 Datum parameterNames,
  78                                 List *parameterDefaults,
  79                                 Datum proconfig,
  80                                 float4 procost,
  81                                 float4 prorows)
  82 {
  83         Oid                     retval;
  84         int                     parameterCount;
  85         int                     allParamCount;
  86         Oid                *allParams;
  87         bool            genericInParam = false;
  88         bool            genericOutParam = false;
  89         bool            internalInParam = false;
  90         bool            internalOutParam = false;
  91         Oid                     variadicType = InvalidOid;
  92         Relation        rel;
  93         HeapTuple       tup;
  94         HeapTuple       oldtup;
  95         bool            nulls[Natts_pg_proc];
  96         Datum           values[Natts_pg_proc];
  97         bool            replaces[Natts_pg_proc];
  98         Oid                     relid;
  99         NameData        procname;
 100         TupleDesc       tupDesc;
 101         bool            is_update;
 102         ObjectAddress myself,
 103                                 referenced;
 104         int                     i;
 105
 106         /*
 107          * sanity checks
 108          */
 109         Assert(PointerIsValid(prosrc));
 110
 111         parameterCount = parameterTypes->dim1;
 112         if (parameterCount < 0 || parameterCount > FUNC_MAX_ARGS)
 113                 ereport(ERROR,
 114                                 (errcode(ERRCODE_TOO_MANY_ARGUMENTS),
 115                                  errmsg(ngettext("functions cannot have more than %d argument",
 116                                                                  "functions cannot have more than %d arguments",
 117                                                                  FUNC_MAX_ARGS),
 118                                                 FUNC_MAX_ARGS)));
 119         /* note: the above is correct, we do NOT count output arguments */
 120
 121         if (allParameterTypes != PointerGetDatum(NULL))
 122         {
 123                 /*
 124                  * We expect the array to be a 1-D OID array; verify that. We don't
 125                  * need to use deconstruct_array() since the array data is just going
 126                  * to look like a C array of OID values.
 127                  */
 128                 ArrayType  *allParamArray = (ArrayType *) DatumGetPointer(allParameterTypes);
 129
 130                 allParamCount = ARR_DIMS(allParamArray)[0];
 131                 if (ARR_NDIM(allParamArray) != 1 ||
 132                         allParamCount <= 0 ||
 133                         ARR_HASNULL(allParamArray) ||
 134                         ARR_ELEMTYPE(allParamArray) != OIDOID)
 135                         elog(ERROR, "allParameterTypes is not a 1-D Oid array");
 136                 allParams = (Oid *) ARR_DATA_PTR(allParamArray);
 137                 Assert(allParamCount >= parameterCount);
 138                 /* we assume caller got the contents right */
 139         }
 140         else
 141         {
 142                 allParamCount = parameterCount;
 143                 allParams = parameterTypes->values;
 144         }
 145
 146         /*
 147          * Do not allow polymorphic return type unless at least one input argument
 148          * is polymorphic.      Also, do not allow return type INTERNAL unless at
 149          * least one input argument is INTERNAL.
 150          */
 151         for (i = 0; i < parameterCount; i++)
 152         {
 153                 switch (parameterTypes->values[i])
 154                 {
 155                         case ANYARRAYOID:
 156                         case ANYELEMENTOID:
 157                         case ANYNONARRAYOID:
 158                         case ANYENUMOID:
 159                                 genericInParam = true;
 160                                 break;
 161                         case INTERNALOID:
 162                                 internalInParam = true;
 163                                 break;
 164                 }
 165         }
 166
 167         if (allParameterTypes != PointerGetDatum(NULL))
 168         {
 169                 for (i = 0; i < allParamCount; i++)
 170                 {
 171                         /*
 172                          * We don't bother to distinguish input and output params here, so
 173                          * if there is, say, just an input INTERNAL param then we will
 174                          * still set internalOutParam.  This is OK since we don't really
 175                          * care.
 176                          */
 177                         switch (allParams[i])
 178                         {
 179                                 case ANYARRAYOID:
 180                                 case ANYELEMENTOID:
 181                                 case ANYNONARRAYOID:
 182                                 case ANYENUMOID:
 183                                         genericOutParam = true;
 184                                         break;
 185                                 case INTERNALOID:
 186                                         internalOutParam = true;
 187                                         break;
 188                         }
 189                 }
 190         }
 191
 192         if ((IsPolymorphicType(returnType) || genericOutParam)
 193                 && !genericInParam)
 194                 ereport(ERROR,
 195                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 196                                  errmsg("cannot determine result data type"),
 197                                  errdetail("A function returning a polymorphic type must have at least one polymorphic argument.")));
 198
 199         if ((returnType == INTERNALOID || internalOutParam) && !internalInParam)
 200                 ereport(ERROR,
 201                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 202                                  errmsg("unsafe use of pseudo-type \"internal\""),
 203                                  errdetail("A function returning \"internal\" must have at least one \"internal\" argument.")));
 204
 205         /*
 206          * don't allow functions of complex types that have the same name as
 207          * existing attributes of the type
 208          */
 209         if (parameterCount == 1 &&
 210                 OidIsValid(parameterTypes->values[0]) &&
 211                 (relid = typeidTypeRelid(parameterTypes->values[0])) != InvalidOid &&
 212                 get_attnum(relid, procedureName) != InvalidAttrNumber)
 213                 ereport(ERROR,
 214                                 (errcode(ERRCODE_DUPLICATE_COLUMN),
 215                                  errmsg("\"%s\" is already an attribute of type %s",
 216                                                 procedureName,
 217                                                 format_type_be(parameterTypes->values[0]))));
 218
 219         if (parameterModes != PointerGetDatum(NULL))
 220         {
 221                 /*
 222                  * We expect the array to be a 1-D CHAR array; verify that. We don't
 223                  * need to use deconstruct_array() since the array data is just going
 224                  * to look like a C array of char values.
 225                  */
 226                 ArrayType  *modesArray = (ArrayType *) DatumGetPointer(parameterModes);
 227                 char       *modes;
 228
 229                 if (ARR_NDIM(modesArray) != 1 ||
 230                         ARR_DIMS(modesArray)[0] != allParamCount ||
 231                         ARR_HASNULL(modesArray) ||
 232                         ARR_ELEMTYPE(modesArray) != CHAROID)
 233                         elog(ERROR, "parameterModes is not a 1-D char array");
 234                 modes = (char *) ARR_DATA_PTR(modesArray);
 235                 /*
 236                  * Only the last input parameter can be variadic; if it is, save
 237                  * its element type.  Errors here are just elog since caller should
 238                  * have checked this already.
 239                  */
 240                 for (i = 0; i < allParamCount; i++)
 241                 {
 242                         switch (modes[i])
 243                         {
 244                                 case PROARGMODE_IN:
 245                                 case PROARGMODE_INOUT:
 246                                         if (OidIsValid(variadicType))
 247                                                 elog(ERROR, "variadic parameter must be last");
 248                                         break;
 249                                 case PROARGMODE_OUT:
 250                                 case PROARGMODE_TABLE:
 251                                         /* okay */
 252                                         break;
 253                                 case PROARGMODE_VARIADIC:
 254                                         if (OidIsValid(variadicType))
 255                                                 elog(ERROR, "variadic parameter must be last");
 256                                         switch (allParams[i])
 257                                         {
 258                                                 case ANYOID:
 259                                                         variadicType = ANYOID;
 260                                                         break;
 261                                                 case ANYARRAYOID:
 262                                                         variadicType = ANYELEMENTOID;
 263                                                         break;
 264                                                 default:
 265                                                         variadicType = get_element_type(allParams[i]);
 266                                                         if (!OidIsValid(variadicType))
 267                                                                 elog(ERROR, "variadic parameter is not an array");
 268                                                         break;
 269                                         }
 270                                         break;
 271                                 default:
 272                                         elog(ERROR, "invalid parameter mode '%c'", modes[i]);
 273                                         break;
 274                         }
 275                 }
 276         }
 277
 278         /*
 279          * All seems OK; prepare the data to be inserted into pg_proc.
 280          */
 281
 282         for (i = 0; i < Natts_pg_proc; ++i)
 283         {
 284                 nulls[i] = false;
 285                 values[i] = (Datum) 0;
 286                 replaces[i] = true;
 287         }
 288
 289         namestrcpy(&procname, procedureName);
 290         values[Anum_pg_proc_proname - 1] = NameGetDatum(&procname);
 291         values[Anum_pg_proc_pronamespace - 1] = ObjectIdGetDatum(procNamespace);
 292         values[Anum_pg_proc_proowner - 1] = ObjectIdGetDatum(GetUserId());
 293         values[Anum_pg_proc_prolang - 1] = ObjectIdGetDatum(languageObjectId);
 294         values[Anum_pg_proc_procost - 1] = Float4GetDatum(procost);
 295         values[Anum_pg_proc_prorows - 1] = Float4GetDatum(prorows);
 296         values[Anum_pg_proc_provariadic - 1] = ObjectIdGetDatum(variadicType);
 297         values[Anum_pg_proc_proisagg - 1] = BoolGetDatum(isAgg);
 298         values[Anum_pg_proc_proiswindow - 1] = BoolGetDatum(isWindowFunc);
 299         values[Anum_pg_proc_prosecdef - 1] = BoolGetDatum(security_definer);
 300         values[Anum_pg_proc_proisstrict - 1] = BoolGetDatum(isStrict);
 301         values[Anum_pg_proc_proretset - 1] = BoolGetDatum(returnsSet);
 302         values[Anum_pg_proc_provolatile - 1] = CharGetDatum(volatility);
 303         values[Anum_pg_proc_pronargs - 1] = UInt16GetDatum(parameterCount);
 304         values[Anum_pg_proc_pronargdefaults - 1] = UInt16GetDatum(list_length(parameterDefaults));
 305         values[Anum_pg_proc_prorettype - 1] = ObjectIdGetDatum(returnType);
 306         values[Anum_pg_proc_proargtypes - 1] = PointerGetDatum(parameterTypes);
 307         if (allParameterTypes != PointerGetDatum(NULL))
 308                 values[Anum_pg_proc_proallargtypes - 1] = allParameterTypes;
 309         else
 310                 nulls[Anum_pg_proc_proallargtypes - 1] = true;
 311         if (parameterModes != PointerGetDatum(NULL))
 312                 values[Anum_pg_proc_proargmodes - 1] = parameterModes;
 313         else
 314                 nulls[Anum_pg_proc_proargmodes - 1] = true;
 315         if (parameterNames != PointerGetDatum(NULL))
 316                 values[Anum_pg_proc_proargnames - 1] = parameterNames;
 317         else
 318                 nulls[Anum_pg_proc_proargnames - 1] = true;
 319         if (parameterDefaults != NIL)
 320                 values[Anum_pg_proc_proargdefaults - 1] = CStringGetTextDatum(nodeToString(parameterDefaults));
 321         else
 322                 nulls[Anum_pg_proc_proargdefaults - 1] = true;
 323         values[Anum_pg_proc_prosrc - 1] = CStringGetTextDatum(prosrc);
 324         if (probin)
 325                 values[Anum_pg_proc_probin - 1] = CStringGetTextDatum(probin);
 326         else
 327                 nulls[Anum_pg_proc_probin - 1] = true;
 328         if (proconfig != PointerGetDatum(NULL))
 329                 values[Anum_pg_proc_proconfig - 1] = proconfig;
 330         else
 331                 nulls[Anum_pg_proc_proconfig - 1] = true;
 332         /* start out with empty permissions */
 333         nulls[Anum_pg_proc_proacl - 1] = true;
 334
 335         rel = heap_open(ProcedureRelationId, RowExclusiveLock);
 336         tupDesc = RelationGetDescr(rel);
 337
 338         /* Check for pre-existing definition */
 339         oldtup = SearchSysCache(PROCNAMEARGSNSP,
 340                                                         PointerGetDatum(procedureName),
 341                                                         PointerGetDatum(parameterTypes),
 342                                                         ObjectIdGetDatum(procNamespace),
 343                                                         0);
 344
 345         if (HeapTupleIsValid(oldtup))
 346         {
 347                 /* There is one; okay to replace it? */
 348                 Form_pg_proc oldproc = (Form_pg_proc) GETSTRUCT(oldtup);
 349
 350                 if (!replace)
 351                         ereport(ERROR,
 352                                         (errcode(ERRCODE_DUPLICATE_FUNCTION),
 353                         errmsg("function \"%s\" already exists with same argument types",
 354                                    procedureName)));
 355                 if (!pg_proc_ownercheck(HeapTupleGetOid(oldtup), GetUserId()))
 356                         aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_PROC,
 357                                                    procedureName);
 358
 359                 /*
 360                  * Not okay to change the return type of the existing proc, since
 361                  * existing rules, views, etc may depend on the return type.
 362                  */
 363                 if (returnType != oldproc->prorettype ||
 364                         returnsSet != oldproc->proretset)
 365                         ereport(ERROR,
 366                                         (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 367                                          errmsg("cannot change return type of existing function"),
 368                                          errhint("Use DROP FUNCTION first.")));
 369
 370                 /*
 371                  * If it returns RECORD, check for possible change of record type
 372                  * implied by OUT parameters
 373                  */
 374                 if (returnType == RECORDOID)
 375                 {
 376                         TupleDesc       olddesc;
 377                         TupleDesc       newdesc;
 378
 379                         olddesc = build_function_result_tupdesc_t(oldtup);
 380                         newdesc = build_function_result_tupdesc_d(allParameterTypes,
 381                                                                                                           parameterModes,
 382                                                                                                           parameterNames);
 383                         if (olddesc == NULL && newdesc == NULL)
 384                                  /* ok, both are runtime-defined RECORDs */ ;
 385                         else if (olddesc == NULL || newdesc == NULL ||
 386                                          !equalTupleDescs(olddesc, newdesc))
 387                                 ereport(ERROR,
 388                                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 389                                         errmsg("cannot change return type of existing function"),
 390                                 errdetail("Row type defined by OUT parameters is different."),
 391                                                  errhint("Use DROP FUNCTION first.")));
 392                 }
 393
 394                 /*
 395                  * If there are existing defaults, check compatibility: redefinition
 396                  * must not remove any defaults nor change their types.  (Removing
 397                  * a default might cause a function to fail to satisfy an existing
 398                  * call.  Changing type would only be possible if the associated
 399                  * parameter is polymorphic, and in such cases a change of default
 400                  * type might alter the resolved output type of existing calls.)
 401                  */
 402                 if (oldproc->pronargdefaults != 0)
 403                 {
 404                         Datum           proargdefaults;
 405                         bool            isnull;
 406                         List       *oldDefaults;
 407                         ListCell   *oldlc;
 408                         ListCell   *newlc;
 409
 410                         if (list_length(parameterDefaults) < oldproc->pronargdefaults)
 411                                 ereport(ERROR,
 412                                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 413                                                  errmsg("cannot remove parameter defaults from existing function"),
 414                                                  errhint("Use DROP FUNCTION first.")));
 415
 416                         proargdefaults = SysCacheGetAttr(PROCNAMEARGSNSP, oldtup,
 417                                                                                          Anum_pg_proc_proargdefaults,
 418                                                                                          &isnull);
 419                         Assert(!isnull);
 420                         oldDefaults = (List *) stringToNode(TextDatumGetCString(proargdefaults));
 421                         Assert(IsA(oldDefaults, List));
 422                         Assert(list_length(oldDefaults) == oldproc->pronargdefaults);
 423
 424                         /* new list can have more defaults than old, advance over 'em */
 425                         newlc = list_head(parameterDefaults);
 426                         for (i = list_length(parameterDefaults) - oldproc->pronargdefaults;
 427                                  i > 0;
 428                                  i--)
 429                                 newlc = lnext(newlc);
 430
 431                         foreach(oldlc, oldDefaults)
 432                         {
 433                                 Node   *oldDef = (Node *) lfirst(oldlc);
 434                                 Node   *newDef = (Node *) lfirst(newlc);
 435
 436                                 if (exprType(oldDef) != exprType(newDef))
 437                                         ereport(ERROR,
 438                                                         (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 439                                                          errmsg("cannot change data type of existing parameter default value"),
 440                                                          errhint("Use DROP FUNCTION first.")));
 441                                 newlc = lnext(newlc);
 442                         }
 443                 }
 444
 445                 /* Can't change aggregate or window-function status, either */
 446                 if (oldproc->proisagg != isAgg)
 447                 {
 448                         if (oldproc->proisagg)
 449                                 ereport(ERROR,
 450                                                 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
 451                                                  errmsg("function \"%s\" is an aggregate function",
 452                                                                 procedureName)));
 453                         else
 454                                 ereport(ERROR,
 455                                                 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
 456                                                  errmsg("function \"%s\" is not an aggregate function",
 457                                                                 procedureName)));
 458                 }
 459                 if (oldproc->proiswindow != isWindowFunc)
 460                 {
 461                         if (oldproc->proiswindow)
 462                                 ereport(ERROR,
 463                                                 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
 464                                                  errmsg("function \"%s\" is a window function",
 465                                                                 procedureName)));
 466                         else
 467                                 ereport(ERROR,
 468                                                 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
 469                                                  errmsg("function \"%s\" is not a window function",
 470                                                                 procedureName)));
 471                 }
 472
 473                 /* do not change existing ownership or permissions, either */
 474                 replaces[Anum_pg_proc_proowner - 1] = false;
 475                 replaces[Anum_pg_proc_proacl - 1] = false;
 476
 477                 /* Okay, do it... */
 478                 tup = heap_modify_tuple(oldtup, tupDesc, values, nulls, replaces);
 479                 simple_heap_update(rel, &tup->t_self, tup);
 480
 481                 ReleaseSysCache(oldtup);
 482                 is_update = true;
 483         }
 484         else
 485         {
 486                 /* Creating a new procedure */
 487                 tup = heap_form_tuple(tupDesc, values, nulls);
 488                 simple_heap_insert(rel, tup);
 489                 is_update = false;
 490         }
 491
 492         /* Need to update indexes for either the insert or update case */
 493         CatalogUpdateIndexes(rel, tup);
 494
 495         retval = HeapTupleGetOid(tup);
 496
 497         /*
 498          * Create dependencies for the new function.  If we are updating an
 499          * existing function, first delete any existing pg_depend entries.
 500          */
 501         if (is_update)
 502         {
 503                 deleteDependencyRecordsFor(ProcedureRelationId, retval);
 504                 deleteSharedDependencyRecordsFor(ProcedureRelationId, retval, 0);
 505         }
 506
 507         myself.classId = ProcedureRelationId;
 508         myself.objectId = retval;
 509         myself.objectSubId = 0;
 510
 511         /* dependency on namespace */
 512         referenced.classId = NamespaceRelationId;
 513         referenced.objectId = procNamespace;
 514         referenced.objectSubId = 0;
 515         recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 516
 517         /* dependency on implementation language */
 518         referenced.classId = LanguageRelationId;
 519         referenced.objectId = languageObjectId;
 520         referenced.objectSubId = 0;
 521         recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 522
 523         /* dependency on return type */
 524         referenced.classId = TypeRelationId;
 525         referenced.objectId = returnType;
 526         referenced.objectSubId = 0;
 527         recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 528
 529         /* dependency on parameter types */
 530         for (i = 0; i < allParamCount; i++)
 531         {
 532                 referenced.classId = TypeRelationId;
 533                 referenced.objectId = allParams[i];
 534                 referenced.objectSubId = 0;
 535                 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 536         }
 537
 538         /* dependency on owner */
 539         recordDependencyOnOwner(ProcedureRelationId, retval, GetUserId());
 540
 541         heap_freetuple(tup);
 542
 543         heap_close(rel, RowExclusiveLock);
 544
 545         /* Verify function body */
 546         if (OidIsValid(languageValidator))
 547         {
 548                 /* Advance command counter so new tuple can be seen by validator */
 549                 CommandCounterIncrement();
 550                 OidFunctionCall1(languageValidator, ObjectIdGetDatum(retval));
 551         }
 552
 553         return retval;
 554 }
 555
 556
 557
 558 /*
 559  * Validator for internal functions
 560  *
 561  * Check that the given internal function name (the "prosrc" value) is
 562  * a known builtin function.
 563  */
 564 Datum
 565 fmgr_internal_validator(PG_FUNCTION_ARGS)
 566 {
 567         Oid                     funcoid = PG_GETARG_OID(0);
 568         HeapTuple       tuple;
 569         Form_pg_proc proc;
 570         bool            isnull;
 571         Datum           tmp;
 572         char       *prosrc;
 573
 574         /*
 575          * We do not honor check_function_bodies since it's unlikely the function
 576          * name will be found later if it isn't there now.
 577          */
 578
 579         tuple = SearchSysCache(PROCOID,
 580                                                    ObjectIdGetDatum(funcoid),
 581                                                    0, 0, 0);
 582         if (!HeapTupleIsValid(tuple))
 583                 elog(ERROR, "cache lookup failed for function %u", funcoid);
 584         proc = (Form_pg_proc) GETSTRUCT(tuple);
 585
 586         tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
 587         if (isnull)
 588                 elog(ERROR, "null prosrc");
 589         prosrc = TextDatumGetCString(tmp);
 590
 591         if (fmgr_internal_function(prosrc) == InvalidOid)
 592                 ereport(ERROR,
 593                                 (errcode(ERRCODE_UNDEFINED_FUNCTION),
 594                                  errmsg("there is no built-in function named \"%s\"",
 595                                                 prosrc)));
 596
 597         ReleaseSysCache(tuple);
 598
 599         PG_RETURN_VOID();
 600 }
 601
 602
 603
 604 /*
 605  * Validator for C language functions
 606  *
 607  * Make sure that the library file exists, is loadable, and contains
 608  * the specified link symbol. Also check for a valid function
 609  * information record.
 610  */
 611 Datum
 612 fmgr_c_validator(PG_FUNCTION_ARGS)
 613 {
 614         Oid                     funcoid = PG_GETARG_OID(0);
 615         void       *libraryhandle;
 616         HeapTuple       tuple;
 617         Form_pg_proc proc;
 618         bool            isnull;
 619         Datum           tmp;
 620         char       *prosrc;
 621         char       *probin;
 622
 623         /*
 624          * It'd be most consistent to skip the check if !check_function_bodies,
 625          * but the purpose of that switch is to be helpful for pg_dump loading,
 626          * and for pg_dump loading it's much better if we *do* check.
 627          */
 628
 629         tuple = SearchSysCache(PROCOID,
 630                                                    ObjectIdGetDatum(funcoid),
 631                                                    0, 0, 0);
 632         if (!HeapTupleIsValid(tuple))
 633                 elog(ERROR, "cache lookup failed for function %u", funcoid);
 634         proc = (Form_pg_proc) GETSTRUCT(tuple);
 635
 636         tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
 637         if (isnull)
 638                 elog(ERROR, "null prosrc for C function %u", funcoid);
 639         prosrc = TextDatumGetCString(tmp);
 640
 641         tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_probin, &isnull);
 642         if (isnull)
 643                 elog(ERROR, "null probin for C function %u", funcoid);
 644         probin = TextDatumGetCString(tmp);
 645
 646         (void) load_external_function(probin, prosrc, true, &libraryhandle);
 647         (void) fetch_finfo_record(libraryhandle, prosrc);
 648
 649         ReleaseSysCache(tuple);
 650
 651         PG_RETURN_VOID();
 652 }
 653
 654
 655 /*
 656  * Validator for SQL language functions
 657  *
 658  * Parse it here in order to be sure that it contains no syntax errors.
 659  */
 660 Datum
 661 fmgr_sql_validator(PG_FUNCTION_ARGS)
 662 {
 663         Oid                     funcoid = PG_GETARG_OID(0);
 664         HeapTuple       tuple;
 665         Form_pg_proc proc;
 666         List       *querytree_list;
 667         bool            isnull;
 668         Datum           tmp;
 669         char       *prosrc;
 670         ErrorContextCallback sqlerrcontext;
 671         bool            haspolyarg;
 672         int                     i;
 673
 674         tuple = SearchSysCache(PROCOID,
 675                                                    ObjectIdGetDatum(funcoid),
 676                                                    0, 0, 0);
 677         if (!HeapTupleIsValid(tuple))
 678                 elog(ERROR, "cache lookup failed for function %u", funcoid);
 679         proc = (Form_pg_proc) GETSTRUCT(tuple);
 680
 681         /* Disallow pseudotype result */
 682         /* except for RECORD, VOID, or polymorphic */
 683         if (get_typtype(proc->prorettype) == TYPTYPE_PSEUDO &&
 684                 proc->prorettype != RECORDOID &&
 685                 proc->prorettype != VOIDOID &&
 686                 !IsPolymorphicType(proc->prorettype))
 687                 ereport(ERROR,
 688                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 689                                  errmsg("SQL functions cannot return type %s",
 690                                                 format_type_be(proc->prorettype))));
 691
 692         /* Disallow pseudotypes in arguments */
 693         /* except for polymorphic */
 694         haspolyarg = false;
 695         for (i = 0; i < proc->pronargs; i++)
 696         {
 697                 if (get_typtype(proc->proargtypes.values[i]) == TYPTYPE_PSEUDO)
 698                 {
 699                         if (IsPolymorphicType(proc->proargtypes.values[i]))
 700                                 haspolyarg = true;
 701                         else
 702                                 ereport(ERROR,
 703                                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 704                                          errmsg("SQL functions cannot have arguments of type %s",
 705                                                         format_type_be(proc->proargtypes.values[i]))));
 706                 }
 707         }
 708
 709         /* Postpone body checks if !check_function_bodies */
 710         if (check_function_bodies)
 711         {
 712                 tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
 713                 if (isnull)
 714                         elog(ERROR, "null prosrc");
 715
 716                 prosrc = TextDatumGetCString(tmp);
 717
 718                 /*
 719                  * Setup error traceback support for ereport().
 720                  */
 721                 sqlerrcontext.callback = sql_function_parse_error_callback;
 722                 sqlerrcontext.arg = tuple;
 723                 sqlerrcontext.previous = error_context_stack;
 724                 error_context_stack = &sqlerrcontext;
 725
 726                 /*
 727                  * We can't do full prechecking of the function definition if there
 728                  * are any polymorphic input types, because actual datatypes of
 729                  * expression results will be unresolvable.  The check will be done at
 730                  * runtime instead.
 731                  *
 732                  * We can run the text through the raw parser though; this will at
 733                  * least catch silly syntactic errors.
 734                  */
 735                 if (!haspolyarg)
 736                 {
 737                         querytree_list = pg_parse_and_rewrite(prosrc,
 738                                                                                                   proc->proargtypes.values,
 739                                                                                                   proc->pronargs);
 740                         (void) check_sql_fn_retval(funcoid, proc->prorettype,
 741                                                                            querytree_list,
 742                                                                            false, NULL);
 743                 }
 744                 else
 745                         querytree_list = pg_parse_query(prosrc);
 746
 747                 error_context_stack = sqlerrcontext.previous;
 748         }
 749
 750         ReleaseSysCache(tuple);
 751
 752         PG_RETURN_VOID();
 753 }
 754
 755 /*
 756  * Error context callback for handling errors in SQL function definitions
 757  */
 758 static void
 759 sql_function_parse_error_callback(void *arg)
 760 {
 761         HeapTuple       tuple = (HeapTuple) arg;
 762         Form_pg_proc proc = (Form_pg_proc) GETSTRUCT(tuple);
 763         bool            isnull;
 764         Datum           tmp;
 765         char       *prosrc;
 766
 767         /* See if it's a syntax error; if so, transpose to CREATE FUNCTION */
 768         tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
 769         if (isnull)
 770                 elog(ERROR, "null prosrc");
 771         prosrc = TextDatumGetCString(tmp);
 772
 773         if (!function_parse_error_transpose(prosrc))
 774         {
 775                 /* If it's not a syntax error, push info onto context stack */
 776                 errcontext("SQL function \"%s\"", NameStr(proc->proname));
 777         }
 778
 779         pfree(prosrc);
 780 }
 781
 782 /*
 783  * Adjust a syntax error occurring inside the function body of a CREATE
 784  * FUNCTION command.  This can be used by any function validator, not only
 785  * for SQL-language functions.  It is assumed that the syntax error position
 786  * is initially relative to the function body string (as passed in).  If
 787  * possible, we adjust the position to reference the original CREATE command;
 788  * if we can't manage that, we set up an "internal query" syntax error instead.
 789  *
 790  * Returns true if a syntax error was processed, false if not.
 791  */
 792 bool
 793 function_parse_error_transpose(const char *prosrc)
 794 {
 795         int                     origerrposition;
 796         int                     newerrposition;
 797         const char *queryText;
 798
 799         /*
 800          * Nothing to do unless we are dealing with a syntax error that has a
 801          * cursor position.
 802          *
 803          * Some PLs may prefer to report the error position as an internal error
 804          * to begin with, so check that too.
 805          */
 806         origerrposition = geterrposition();
 807         if (origerrposition <= 0)
 808         {
 809                 origerrposition = getinternalerrposition();
 810                 if (origerrposition <= 0)
 811                         return false;
 812         }
 813
 814         /* We can get the original query text from the active portal (hack...) */
 815         Assert(ActivePortal && ActivePortal->status == PORTAL_ACTIVE);
 816         queryText = ActivePortal->sourceText;
 817
 818         /* Try to locate the prosrc in the original text */
 819         newerrposition = match_prosrc_to_query(prosrc, queryText, origerrposition);
 820
 821         if (newerrposition > 0)
 822         {
 823                 /* Successful, so fix error position to reference original query */
 824                 errposition(newerrposition);
 825                 /* Get rid of any report of the error as an "internal query" */
 826                 internalerrposition(0);
 827                 internalerrquery(NULL);
 828         }
 829         else
 830         {
 831                 /*
 832                  * If unsuccessful, convert the position to an internal position
 833                  * marker and give the function text as the internal query.
 834                  */
 835                 errposition(0);
 836                 internalerrposition(origerrposition);
 837                 internalerrquery(prosrc);
 838         }
 839
 840         return true;
 841 }
 842
 843 /*
 844  * Try to locate the string literal containing the function body in the
 845  * given text of the CREATE FUNCTION command.  If successful, return the
 846  * character (not byte) index within the command corresponding to the
 847  * given character index within the literal.  If not successful, return 0.
 848  */
 849 static int
 850 match_prosrc_to_query(const char *prosrc, const char *queryText,
 851                                           int cursorpos)
 852 {
 853         /*
 854          * Rather than fully parsing the CREATE FUNCTION command, we just scan the
 855          * command looking for $prosrc$ or 'prosrc'.  This could be fooled (though
 856          * not in any very probable scenarios), so fail if we find more than one
 857          * match.
 858          */
 859         int                     prosrclen = strlen(prosrc);
 860         int                     querylen = strlen(queryText);
 861         int                     matchpos = 0;
 862         int                     curpos;
 863         int                     newcursorpos;
 864
 865         for (curpos = 0; curpos < querylen - prosrclen; curpos++)
 866         {
 867                 if (queryText[curpos] == '$' &&
 868                         strncmp(prosrc, &queryText[curpos + 1], prosrclen) == 0 &&
 869                         queryText[curpos + 1 + prosrclen] == '$')
 870                 {
 871                         /*
 872                          * Found a $foo$ match.  Since there are no embedded quoting
 873                          * characters in a dollar-quoted literal, we don't have to do any
 874                          * fancy arithmetic; just offset by the starting position.
 875                          */
 876                         if (matchpos)
 877                                 return 0;               /* multiple matches, fail */
 878                         matchpos = pg_mbstrlen_with_len(queryText, curpos + 1)
 879                                 + cursorpos;
 880                 }
 881                 else if (queryText[curpos] == '\'' &&
 882                                  match_prosrc_to_literal(prosrc, &queryText[curpos + 1],
 883                                                                                  cursorpos, &newcursorpos))
 884                 {
 885                         /*
 886                          * Found a 'foo' match.  match_prosrc_to_literal() has adjusted
 887                          * for any quotes or backslashes embedded in the literal.
 888                          */
 889                         if (matchpos)
 890                                 return 0;               /* multiple matches, fail */
 891                         matchpos = pg_mbstrlen_with_len(queryText, curpos + 1)
 892                                 + newcursorpos;
 893                 }
 894         }
 895
 896         return matchpos;
 897 }
 898
 899 /*
 900  * Try to match the given source text to a single-quoted literal.
 901  * If successful, adjust newcursorpos to correspond to the character
 902  * (not byte) index corresponding to cursorpos in the source text.
 903  *
 904  * At entry, literal points just past a ' character.  We must check for the
 905  * trailing quote.
 906  */
 907 static bool
 908 match_prosrc_to_literal(const char *prosrc, const char *literal,
 909                                                 int cursorpos, int *newcursorpos)
 910 {
 911         int                     newcp = cursorpos;
 912         int                     chlen;
 913
 914         /*
 915          * This implementation handles backslashes and doubled quotes in the
 916          * string literal.      It does not handle the SQL syntax for literals
 917          * continued across line boundaries.
 918          *
 919          * We do the comparison a character at a time, not a byte at a time, so
 920          * that we can do the correct cursorpos math.
 921          */
 922         while (*prosrc)
 923         {
 924                 cursorpos--;                    /* characters left before cursor */
 925
 926                 /*
 927                  * Check for backslashes and doubled quotes in the literal; adjust
 928                  * newcp when one is found before the cursor.
 929                  */
 930                 if (*literal == '\\')
 931                 {
 932                         literal++;
 933                         if (cursorpos > 0)
 934                                 newcp++;
 935                 }
 936                 else if (*literal == '\'')
 937                 {
 938                         if (literal[1] != '\'')
 939                                 goto fail;
 940                         literal++;
 941                         if (cursorpos > 0)
 942                                 newcp++;
 943                 }
 944                 chlen = pg_mblen(prosrc);
 945                 if (strncmp(prosrc, literal, chlen) != 0)
 946                         goto fail;
 947                 prosrc += chlen;
 948                 literal += chlen;
 949         }
 950
 951         if (*literal == '\'' && literal[1] != '\'')
 952         {
 953                 /* success */
 954                 *newcursorpos = newcp;
 955                 return true;
 956         }
 957
 958 fail:
 959         /* Must set *newcursorpos to suppress compiler warning */
 960         *newcursorpos = newcp;
 961         return false;
 962 }